[SciPy-User] calculating the mean for each factor (like tapply in R)

Hi there,
I've just moved from R to IPython and wondered if there was a good way of finding the means and/or variance of values in a dataframe given a factor
e.g.:
if df =
x experiment
10 1
13 1
12 1
3 2
4 2
6 2
33 3
44 3
55 3
in tapply you would do:
tapply(df$x, list(df$experiment), mean)
tapply(df$x, list(df$experiment), var)
I guess I can always loop through the array for each experiment type, but thought that this is the kind of functionality that would be included in a core library.
Many thanks,
Ben